//@version=3
//created by kruk
study(«3MA&BB», overlay=true)
len_MA = input(9,title = «SMA period»)
len_EMA = input(9, title = «EMA period»)
len_WMA = input(9, title = «WMA period»)
len_bb = input(20, title = «BB period»)
mult = input(2, title = «BB stdev multiplier»)

MA = sma(close,len_MA)
EMA = ema(close, len_EMA)
WMA = wma(close, len_WMA)
bb_mid = sma(close,len_bb)
range = stdev(close,len_bb)*mult
bb_up = bb_mid+range
bb_lo = bb_mid-range

plot(MA, color = blue, transp=0, title = «SMA»)
plot(EMA, color = black, transp=0, title = «EMA»)
plot(WMA, color = red, transp=0, title = «WMA»)
bb1=plot(bb_up,color = green, transp = 0, title = «BB upper»)
bb=plot(bb_mid, color = green,transp = 0,title= «BB middle»)
bb2=plot(bb_lo, color = green, transp=0, title = «BB lower»)
fill(bb1,bb2,color=blue,transp=90,title = «BB background»)